48: Oral probiotic versus placebo and the maternal microbiome during pregnancy: A randomized controlled trial

Abstract

The vaginal microbiome likely impacts pregnancy outcomes. There is evidence that certain oral probiotic preparations can influence the vaginal flora. We aim to investigate whether an oral probiotic preparation containing a mixture of Lactobacillus and Bifidobacterium species can change the vaginal microbiome during pregnancy in order to promote protective bacteria. This was a pilot randomized double-blinded placebo-controlled trial conducted at UCSD. Healthy singleton pregnancies were enrolled between 6 weeks 0 days and 13 weeks 6 days gestation, and were randomized to receive an oral probiotic or a placebo pill daily for 4-6 weeks. Samples from the vagina, anus, and urine were obtained prior to randomization and 4-6 weeks after intervention. The V4 region of the 16S rRNA gene was amplified from extracted DNA and sequenced. 48 patients were enrolled, and 43 patients completed the study. 21 were randomized to the probiotic, and 22 were randomized to the placebo. The groups were similar in baseline characteristics and beta diversity for all sample sites. Beta diversity was evaluated using weighted UNIFRAC. There was no statistically significant difference in the beta diversity of the vaginal microbiome for the probiotic group (p=0.877) or for the placebo group (p=0.961) before and after intervention. Similarly, there was no statistically significant difference in the beta diversity of the anal microbiome or the urinary microbiome for the 2 groups. There were 3 patients in the probiotic group who developed vaginal infections requiring treatment during the study period, and therefore these patients were excluded from the microbiome analysis. The overall vaginal microbiome does not change significantly after the introduction of an oral probiotic supplement into the maternal diet. The overall vaginal microbiome appears relatively stable over the course of 4-6 weeks during the first half of pregnancy, and the relative abundance of Lactobacillus and Bifidobacterium, the two genera contained in the probiotic, did not appear to be significantly impacted by the probiotic.View Large Image Figure ViewerDownload Hi-res image Download (PPT)